Chicago — A former federal prosecutor who helped convict Oklahoma City bomber Timothy McVeigh suggests that the great risk of America's growing militia movement is not necessarily in the militias themselves, but in their capacity to spark rogue actors like Mr. McVeigh, whose 1995 attack on the Murrah Federal Building killed 168 people.

Then, as now, the president was a Democrat seen to be liberal (President Clinton versus President Obama). Then, as now, he had recently pushed though a controversial piece of legislation (the federal assault weapons ban versus healthcare reform). And then, as now, an extremist fringe was warning of a pending government takeover.

The rogue actor

Yet the primary danger, Goelman says, is not necessarily when militias spread antigovernment rhetoric, but when they attract outsiders to the group who may be convinced to act on their own.

“Anytime you have group-think and this churning of ridiculous ideas back and forth, eventually you’ll get someone like McVeigh who’s going to say ‘I’m going to take the mantle of leadership and fire the shot heard around the world and start the second American revolution,’ ” says Goelman.

Neither McVeigh nor Mr. Nichols were members of any specific organization, but they were known to associate with hate groups and militias. The associations fueled in McVeigh a sense of self-importance, Goelman says.

McVeigh considered groups like the Michigan Militia “too moderate” and saw himself as “a man of action” who wanted to do more than just vent about the federal government’s standoffs at Ruby Ridge, Idaho, and Waco, Texas, two incidents in 1992 and 1993 that became flashpoints for antigovernment groups.

Militia group-think

Today's militias are much more organized, though not automatically more dangerous because of it. The improved recruiting methods also give law enforcement more opportunities to monitor activities.

Moreover, some militias may actually play a role in helping federal authorities capture outsiders they consider extreme. The FBI indictment referred to “a cooperating witness and an undercover FBI agent.” The Detroit News reports that one of the nine defendants, through her lawyer, said she believes a member of another militia group reported the Hutaree’s plans to the FBI.

If true, it illustrates what Goelman says is the reality of many militias – and why McVeigh, despite his hope that the bombing would be a call-to-arms, failed to become a martyr for the movement: most draw the line between heated rhetoric and actual killing.

“Some of this is fantasy. I think the idea that it is kind of fun to talk about a UN tank on your front lawn and the New World Order … but when someone blows up a building and kills 19 kids in a day-care center, it’s not so glamorous anymore,” he says, referring to the Oklahoma City incident. “The reality of murdering innocent people ends up far less glorious than striking the blow.”